Molecular phylogeny and ultrastructure of Myxobolus cf. cuneus, a parasite of patinga hybrid and Henneguya pseudoplatystoma, a parasite of pintado hybrid

Abstract

Through morphological, histopathological and ultrastructural analysis of Myxobolus cuneus Adriano, Arana et Cordeiro, 2006 and Henneguya pseudoplatystoma Naldoni, Arana, Maia, Ceccarelli, Tavares, Borges, Pozo et Adriano, 2009 were identified infecting pacu respectively (Piaractus mesopotamicus) and hybrid pintado (Pseudoplatystoma corruscans x Pseudoplatystoma reticulatum) taken from Brazilian fish farms. The present study describes 18S rDNA sequencing of Myxobolus cf. cuneus infecting the spleen of farmed patinga, a hybrid fish resulting from the crossing of P. mesopotamicus x Piaractus brachypomus, and H. pseudoplatystoma found in farmed hybrid pintado from the state of Sao Paulo, Brazil. The study also provides new details of the host-parasite interface of M. cf. cuneus, which reveal that the plasmodial wall is composed of a single membrane connected to the plasmodium ectoplasm by numerous pinocytic canals. The plasmodia also displayed asynchronous development but had disporic pansporoblasts at different developmental stages; immature and mature spores were found at different depth levels of the plasmodium. Maximum likelihood phylogenetic analysis showed that M. cf. cuneus appeared as a sister species of Henneguya pellucida Adriano, Arana et Cordeiro, 2005 in a sub-clade composed mainly of myxosporean parasites of characiforms, and that H. pseudoplatystoma clustered in a sub-clade composed of Henneguya/Myxobolus spp. parasites of siluriform fish.

Histopathology and molecular identification of Henneguya pseudoplatystoma

“…When compared to the Henneguya spp. available at the NCBI, the sequence of H. pseudoplatystoma identified in this study, demonstrated 99.6% identity with H. pseudoplatystoma collected from a hybrid surubim (P. corruscans x P. reticulatum) in São Paulo, Brazil (Milanin et al, 2015). Phylogenetic tree constructed, demonstrated that Henneguya species tend to form clades based on the family of the host fish.…”

“…3). On the other hand, species grouped in clade, E were identified as parasitizing the Pimelodidae family members in Brazilian territory, including in the southeast and central-western regions (Naldoni et al, 2011;Adriano et al, 2012;Carriero et al, 2013;Milanin et al, 2015), as well as a single parasite that was isolated in the family Naididae. At last, clade F grouped two families of fish Mugilidae and Naididae.…”

Detecção de mixosporídeos por PCR em Tempo Real e por PCR Convencional em amostras de água de pisciculturas

“…Até o momento, foram descritas 140 de espécies de mixosporídeos, conhecidas por parasitarem peixes de água doce brasileiras de diferentes bacias hidrográficas (ADRIANO & OLIVEIRA, 2018;OKAMURA et al, 2018) e algumas, infectando peixes nativos amplamente cultivados em pisciculturas (ADRIANO et al, 2005a(ADRIANO et al, , 2005b2009a;2009b;EIRAS et al, 2009;MARTINS & SOUZA, 1997;MARTINS, 1997;NALDONI et al, 2009;. Muitas destas descrições foram realizadas por pesquisas desenvolvidas no Laboratório de Imunologia de Parasitas da FZEA-USP (ADRIANO et al, 2005a(ADRIANO et al, , 2005b(ADRIANO et al, , 2006(ADRIANO et al, , 2009(ADRIANO et al, , 2012CAPODIFOGLIO et al,2015CAPODIFOGLIO et al, , 2016CAPODIFOGLIO et al, e 2019CARRIERO 2013;MILANIN et al, 2010MILANIN et al, , 2015a2015b;2018a;MOREIRA et al, 2014;NALDONI et al, 2011NALDONI et al, , 2014NALDONI et al, , 2015.…”

“…Utilizar as técnicas cPCR e qPCR para o diagnóstico de mixosporídeos em amostras de água de pisciculturas. Estas localidades foram escolhidas devido ao fato de que já foram identificados, anteriormente, peixes e oligoquetas infectados por mixosporídeos, como descritos nos trabalhos de Carriero et al, 2011;Milanin et al,2015aMilanin et al, , 2016Moreira et al, 2013. Por esse motivo, as amostras de água coletadas nas pisciculturas foram identificadas como amostras suspeitas.…”